1. Field of Invention
The present invention relates to a connector assembly. More particularly, the present invention relates to a stackable connector assembly.
2. Description of Related Art
Computers have only a half-century long history, but they are evolving with an extremely fast pace. A variety of peripheral device and a variety of transmission interface are introducing with the generations of the CPU to expand the function of the computer or increase the data transmission speed. Moreover, computers have made great progress and have become extremely versatile in the last few years, the number of built-in interfaces on the motherboard are also increased very fast. However, every interface correspond a specific connector as a transporting channel. Therefore, the amount of connector increases very fast. Due to this reason, the stackable connector is introduced to provide multiple interface ports in a restricted area of the motherboard.
Referring to FIG. 1. FIG. 1 is a schematic diagram of a front view of a common stackable connector assembly. A first connector 102 and a second connector 104 are mounted on metal brackets 106. The second connector 104 is arranged above the first connector 102. The metal brackets 106 can increase the strength of the stackable connector assembly 100. A connective line 108 is configured between the second connector 104 and a motherboard 114, and used for transmitting signals between the second connector 104 and the motherboard 114.
FIG. 2 is a schematic diagram of an exploded view of a connector 200. The connector includes a connector body 202, a raised portion 204, and an electrically conductive shell 206. The raised portion 204 protrudes from one side of the connector body 202. The electrically conductive shell 206 is covered on the raised portion 204 and one side of the connector body 202. The electrically conductive shell 206 is used to protect the raised portion 204 from physical harm.
Moreover, the electrically conductive shell 206 also can be a metallic shielding shell and provide EMI shielding. When an external signal cable is connected to the raised portion 204, the electrically conductive shell 206 can shielding the electromagnetic radiation form the raised portion 204 in the data transmission process. Therefore, the electromagnetic radiation can not be radiated from the raised portion 204 toward the outside environment when the high-speed data transmission.
In general, there are two types of interfaces, the high-speed interface and the low-speed interface. The high-speed interface has a higher data transfer rate in unit time, such as VGA port. The low-speed interface has a lower data transfer rate in unit time, such as serial port. Because of the signal integrity, the high-speed interface of the stackable connector assembly is always configured near the motherboard. Therefore, the low-speed interface of the stackable connector assembly is always configured above the high-speed interface connector.
Please refer to FIG. 3. FIG. 3 is a schematic diagram of a side view of a common stackable connector assembly from the A direction of FIG. 1. There is no EMI protection between the first connector 102 and the second connector 104 in the common design of the stackable connector. However, the first connector radiates the strong electromagnetic radiation 304, 306, and 308. When the motherboard is installed in the computer case, the I/O shielding 302 could cover the connectors. Only the raised portions of the connectors protrude from the I/O shielding 302. The I/O shielding 302 is used to prevent dust or foreign matter into the computer case to damage electronic components. Furthermore, the I/O shielding 302 is also in contact with the computer case, and is grounded by the computer case.
The I/O shielding 302 could shield the electromagnetic radiation 304. The other electromagnetic radiation noise 306 and 308 could couple to the second connector 104 and make the signal unstable on second connector.
Therefore, it is desirable to reduce the electromagnetic interference from the high-speed connector of a stackable connector assembly in most cost effective way, and increase the signal stability of the two connectors of a stacked connector.